<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>

</body>
<script>
    function login(){
        console.log(1)
    }
    let o = {
        login(){
            console.log(2)
        },
        submit(){
            // login() // 1
            // o.login // 2
            // this.login() // 2
            // login.call(o)
        }
    }
    o.submit()
</script>
</html>
